FR fertility test???

Cassi • Momma of Three Graci 5-7-15 Graeson 9-7-16 Gabriel 8-6-19! Angel Momma of Two Nov 2015 and Twin B Jan 19 2016!
Has anyone taken this i guess u can get it at the drug store. U take it CD3 while still on AF and itll tell u ur fertility this month??? Any advice